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  #31  
Old 10-08-2014, 11:33 PM
Trevor Gore Trevor Gore is offline
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Quote:
Originally Posted by charles Tauber View Post
If you play your cards right, Mr. Gore, himself, will answer your questions.
...and he turns up like a bad penny...

A nice summary of the evolution of the neck joint, Charles!

A bit of background on the neck joint I use...

It originated from a design by Gerard Gilet who engineered one of the first bolt-on necks, but it had a glued down fretboard extension. Gerard came up with the square brass rod idea, which basically runs up the guts of the heel. It's square so it doesn't wedge the wood and split it as round inserts (barrel bolts, dowels, etc.) are inclined to do. I'd post a pic, but have to put it on another site first... Anyway, if you look at the heel cap of a guitar and imagine a 3/8" square hole in the middle of it, heading for the fretboard, that's where the brass rod is (or aluminium if you want to take some weight out) that the screws thread in to. I couldn't see the point of a bolt-on with glue, so made another tenon for the neck extension. It looks a lot more complicated to build than it actually is.




The tilt neck (user adjustable neck angle) idea has been around since the 19th century, or maybe before, but Johan Stauffer (who CF Martin I apprenticed under) was an early adopter, if not the originator, of the idea.

Here's a pic of one by Martin de Witte which follows the Stauffer concept fairly closely:




My implementation of the design follows the same broad concepts, but, as ever, the differences are in the engineering of the details. Here's some pics of what I do:





There are more pics under "Small Body Classical" in the photo gallery on my website.

This doesn't need tools to adjust the action and is quite easy to build (that's the real secret!) and can be easily (re-)adjusted for yaw, roll and string length (by the builder) with just pitch being user adjustable.

Quote:
Originally Posted by BothHands
Wow. Assuming the knob does what it should, it doesn't get any better than that.
Yep, works real well.

Quote:
Originally Posted by BothHands
So I'm assuming purchase of this guitar by an American would buh-LUDDY EXPENSIVE....I hope you're enjoying Life there in Oz. That's the one place I'd really like to live... Can you offer any advice?.....
You can always pick-up! You wouldn't be the first...
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  #32  
Old 10-09-2014, 11:09 PM
BothHands BothHands is offline
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I appreciate so many colorful Australian expressions. Here's an American expression that applies:

HLY MACKERAL!!!

What a fine piece of engineering, and thanks for clarifying location and other details regarding your square brass (or aluminum) rod. I applaud your decision to include the second mortise-and-tenon and hardware to 1) facilitate tool-free neck-angle adjustment and 2) avoid gluing the fretboard to the guitar's top. For me, this is the ONLY way to go. Being able to remove the neck without "glue issues" is the obvious choice, and while I consider it HUGELY important, it seems you've reduced this factor to a "peripheral benefit" because the blessings of your adjustable neck angle seem to render the need for tradition neck resets moot.

Instead of the old adage, "kill two birds with one stone", I think you've killed two birds by dropping a refrigerator on them! Man!!! Charles said your writings constitute the current state of the art. ICANDIGGIT!

I don't want to unearth any proprietary information, but IF it's not too revealing, can you clarify the following? In your photos there appears to be a dark binding where the neck proper (more or less in line with its tenon face) meets the neck's heal. When the neck is adjusted, it must move in relation to the body, so a "gap" probably occurs somewhere... The illustration below only guesses at the internal workings and the point of rotation. The second view is exaggerated, but by chance, is this what occurs when adjusting the neck backward in relation to the guitar body? Or does movement occur somehow at that dark binding strip across the neck/heal structure.


If you prefer not to answer, and/or if you want me to remove the illustration, just tell me and I'll do so immediately. I don't need to know everything about how this works, but I'd like to understand it for future reference - mostly because I'll find it impossible to commit to purchasing any other expensive guitar after seeing this.

And as for picking one up in Oz, I would have to play one first - so can you build mine in whatever length of time I'd be allowed to stay on a visitor/guest visa? I'm just kidding; I'm sure I couldn't stay long at all. But if you don't mind, I'll email you with serious questions via your website.

Thanks very much for your contributions here.
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  #33  
Old 10-10-2014, 03:30 AM
murrmac123 murrmac123 is offline
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Tom, I do appreciate your enthusiasm for Trevor's superb guitars, but given that he lives in Oz and you are in the US , it may be worthwhile contacting a US builder who offers the facility which you seek.

Kent Chasson also makes guitars with an adjustable neck angle ... and is also a AGF sponsor, although not a prolific poster.

It would be a bit of a hike from Nebraska to Washington, but not as far as from USA to OZ.
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  #34  
Old 10-10-2014, 12:48 PM
BothHands BothHands is offline
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Quote:
Originally Posted by murrmac123 View Post
[...] it may be worthwhile contacting a US builder who offers the facility which you seek.

Kent Chasson also makes guitars with an adjustable neck angle ... and is also a AGF sponsor, although not a prolific poster.

It would be a bit of a hike from Nebraska to Washington, but not as far as from USA to OZ.
Thanks, Murray. Good points, all.

Until recently I played only one acoustic guitar for several decades - the Gurian in question. I'm interested in other guitars now only because I realize now how much easier it is to play a wider neck. So I have no idea "who makes what" here in the US, or anywhere else.

I'll look into Kent Chasson (and others) as you suggest, assuming any build guitars with an adjustable neck similar to Trevor Gore's. Frankly, Mr Gore's design (to the extent I understand it) seems like the answer to most, if not all, the neck-related problems that affect so many acoustic guitars - particularly the USED guitars you and I buy online and then spend $70 to return ship.

I'm a fan of things Australian, and "guitar ownership" is a serious matter - so a truly exceptional Australian guitar would be "a lifetime instrument" for me. I might well be willing to go above and beyond to obtain that. Of course, it'll be a lot easier if a custom/boutique builder is represented by at least one dealer in the United States.

Realistically, by the time I'm ready to buy, I'm pretty sure I'll know what to buy.
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  #35  
Old 10-10-2014, 08:31 PM
Jim.S Jim.S is offline
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Originally Posted by BothHands View Post
Realistically, by the time I'm ready to buy, I'm pretty sure I'll know what to buy.
Ha! I still reckon you will look in the box of chocolates and have a hard time picking which one to eat first.

Quote:
Originally Posted by BothHands View Post

I'm a fan of things Australian, and "guitar ownership" is a serious matter - so a truly exceptional Australian guitar would be "a lifetime instrument" for me. I might well be willing to go above and beyond to obtain that. Of course, it'll be a lot easier if a custom/boutique builder is represented by at least one dealer in the United States.
In a year or so consider a trip to the real Crocodile Dundee's "Never Never Land", You can drop in and play some of my Australian made things, by then I will have a few that will be sold as secondhand (cheap as chips). By second hand I mean they will be played in by me for six months or so before I will part with them or who knows, by then I may have some new ones to sell.

I should also say in a sort of non professional promotional way that I would not build a guitar without a tilt neck and although mine are not tool less it isn't difficult to keep a Allen Key on your key ring.

Jim
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  #36  
Old 10-10-2014, 09:40 PM
Trevor Gore Trevor Gore is offline
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Quote:
Originally Posted by BothHands
The illustration below only guesses at the internal workings and the point of rotation. The second view is exaggerated, but by chance, is this what occurs when adjusting the neck backward in relation to the guitar body?
All of this type of joint work in a similar way: a pivot point somewhere under the body joint fret and some type of adjustment mechanism. So your illustration is pretty right, except you have ringed the wrong pivot point. You have shown the pivot point in your drawing to the right of the place you have ringed. Delete the block which has the ring in the upper left and move the inclined plane toward the neck and other than that, as a concept drawing, it is correct. There are, however, considerable differences in the detailed engineering. The trick, as ever, is not only to make it work effectively, but also to make it simple to manufacture and use. One or two makers use a sliding mechanism (the plane of the fretboard moves "vertically" rather than tilting), which works fine but is quite a lot more complicated to build.

Quote:
Originally Posted by BothHands
When the neck is adjusted, it must move in relation to the body, so a "gap" probably occurs somewhere...
The only gaps are those required for clearance so the neck will actually move. Too much finish and you have a problem... The sides of the heel are perpendicular to the sides of the guitar body for a short distance, so as the neck moves no gaps get larger or smaller. Same with the neck extension over the body. A gap does open beneath the penultimate fret, where the neck wood stops at the upper transverse brace and the fretboard continues on to the sound hole edge.

Quote:
Originally Posted by BothHands
I'm interested in other guitars now only because I realize now how much easier it is to play a wider neck.
Yes, it makes a huge difference. Most of mine are in the 46-47mm wide zone at the nut, but as a custom builder the customer gets to choose anything they want.

Quote:
Originally Posted by Jim.S
In a year or so consider a trip to the real Crocodile Dundee's "Never Never Land"...

Where Jim lives, guitars have a tendency to melt (think Salvador Dali clocks); a combination of high temps and high humidity. That's why he builds with a tilt neck. Just part of what you have to do for guitars to survive at latitude 12 degrees south. He complains of the cold when he's down here in a comfortable 28C, 45% RH!
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  #37  
Old 10-11-2014, 08:07 AM
murrmac123 murrmac123 is offline
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Originally Posted by Trevor Gore View Post
Gerard came up with the square brass rod idea, which basically runs up the guts of the heel. It's square so it doesn't wedge the wood and split it as round inserts (barrel bolts, dowels, etc.) are inclined to do.
I am sure that your design works perfectly , Trevor, but most builders won't have access to a mortising machine to cut the square hole, which I assume is how you do it (you don't drill a hole and then chisel it square surely?)

The tendency for barrel nuts to split the wood of the tenon is admittedly a problem, but can be totally overcome by gluing in two cross- grain cleats, one on either side of the bolt hole. Better still, cleats made of 1.5mm thick aeroply. These cleats should be glued into sawn kerfs, not just stuck onto the cheeks of the tenon.
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  #38  
Old 10-11-2014, 09:22 AM
charles Tauber charles Tauber is offline
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Originally Posted by murrmac123 View Post
most builders won't have access to a mortising machine to cut the square hole...
A drill press mortising attachment will work adequately for that purpose. Last I looked, they ran under $150. Bench-top mortising machines can be had for a few hundred dollars. Probably within the reach of many small-quantity builders.

I suspect that the same design with a round, rather than square, bar would probably work adequately and allow installation into a round hole.
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  #39  
Old 10-11-2014, 10:29 AM
BothHands BothHands is offline
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Originally Posted by Jim.S View Post
Ha! I still reckon you will look in the box of chocolates and have a hard time picking which one to eat first.
Guilty as charged. I guess you know "my type" and I'll bet you worry a bit when building for guys like me. But honestly, I'm very reasonable in my expectations and very appreciative of real quality (and value). And once I understand what the parameters are, I can tell you exactly what I want. I just find that taking the time and trouble to make sure everyone's on the same page BEFORE anyone actually does anything, makes for 'happy endings'. No surprises, no disappointments, one big WIN/WIN.

Quote:
Originally Posted by Jim.S View Post
In a year or so consider a trip to the real Crocodile Dundee's "Never Never Land", You can drop in and play some of my Australian made things, by then I will have a few that will be sold as secondhand (cheap as chips). By second hand I mean they will be played in by me for six months or so before I will part with them or who knows, by then I may have some new ones to sell.
What a fine idea that is, Jim! I've long wanted to visit Australia, and turning that trip into a "hand-built guitar shopping spree" is just TOO, TOO GOOD! Of course, money is the issue, but this is now my goal in terms of international travel.

Quote:
Originally Posted by Jim.S View Post
I should also say in a sort of non professional promotional way that I would not build a guitar without a tilt neck and although mine are not tool less it isn't difficult to keep a Allen Key on your key ring.
You're right. An Allen Key or other small tool is no problem at all.

Jim, you and the other builders/luthiers in this forum must excuse me; I don't know who among you are actually luthiers (now I understand your remark about trying to pry information out of Trevor regarding his neck joint...duh). If focusing on one offends the others that's certainly not my intention. I'm a knowledgeable guitarist and guitar owner, and I assume most members of this forum are like me. That said, if any luthier/builder here would care to enlighten me regarding his/her instruments, send me a PM. I'm located nearly dead-center of the Continental US. The nearer you are to that, the better.

In fact, I just set up a thread inviting ALL custom builders who utilize some form of adjustable neck angle to post their names and contact information to that thread. HERE'S THE LINK. I hope doing so is okay with the forum administration. I totally support this approach and will do whatever I can as a layman to promote it.


Crocodile Dundee
There's a scene in the original movie where Dundee steps in to rescue a girl who's being mugged. Afterward she says, "But weren't you afraid? He had a knife!" Dundee reaches down and retrieves something from his boot, replying, "A knife? That's not a knife. THIS is a knife..." as she stares agape at his gleaming blade, eight times the size of the mugger's puny switchblade.

In light of what I've learned here in the past several days, I think we can and should apply the expression thusly:

That's not a guitar. THIS is a guitar.

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  #40  
Old 10-11-2014, 11:02 AM
BothHands BothHands is offline
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Quote:
Originally Posted by Trevor Gore View Post
[...] So your illustration is pretty right, except you have ringed the wrong pivot point. You have shown the pivot point in your drawing to the right of the place you have ringed.
I see it now. Thanks. I made that drawing pretty late at night... Regardless of the exact workings, yer a bluddy genius, sez I.

Quote:
Originally Posted by Trevor Gore View Post
One or two makers use a sliding mechanism (the plane of the fretboard moves "vertically" rather than tilting), which works fine but is quite a lot more complicated to build.
Writing as a layman, and based only on my own experiences, I'd choose your pivoting design over the alternative as you describe it here.

Quote:
Originally Posted by Trevor Gore View Post
The only gaps are those required for clearance so the neck will actually move. Too much finish and you have a problem... The sides of the heel are perpendicular to the sides of the guitar body for a short distance, so as the neck moves no gaps get larger or smaller. Same with the neck extension over the body. A gap does open beneath the penultimate fret, where the neck wood stops at the upper transverse brace and the fretboard continues on to the sound hole edge.
Thanks for this further description. I'm not a machinist, but I do machine metals in some instances, so I have an appreciation for tolerances and clearances. Wood being wood, I'm guessing you and Jim (and others) must take very seriously your choice of woods and how you finish/seal the moving components - and the wooden structures that support/contain them. I WOULD NEVER ATTEMPT IT MYSELF but I would have every confidence in your implementation. The same goes for Jim.

You're kidding Jim about his climate, and it makes me really think about how the two of you build under such different climatic conditions. Where I live, the summers can be blistering hot and the winters deadly frigid. If I end up buying from either of you, I'll need your assurance that the tremendous temperature/humidity swings in my 'slice of the planet' won't 'jam up' these ingenious designs. I'm sure this is something you both have already taken into consideration, so you needn't respond here (unless you want to ). I just present the notion as 'Food for Thought'.

Quote:
Originally Posted by Trevor Gore View Post
Yes, it [neck width] makes a huge difference. Most of mine are in the 46-47mm wide zone at the nut, but as a custom builder the customer gets to choose anything they want.
Ahhhh! The blessings of FREEDOM! My only problem is trying to find examples of 'other widths' to play beforehand, so I know which to choose for the long run...

Quote:
Originally Posted by Trevor Gore View Post
Where Jim lives, guitars have a tendency to melt (think Salvador Dali clocks); a combination of high temps and high humidity. That's why he builds with a tilt neck. Just part of what you have to do for guitars to survive at latitude 12 degrees south. He complains of the cold when he's down here in a comfortable 28C, 45% RH!
HA! See my remarks several paragraphs above. Thanks a LOT for this discourse.
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  #41  
Old 10-11-2014, 11:11 AM
BothHands BothHands is offline
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Originally Posted by murrmac123 View Post
The tendency for barrel nuts to split the wood of the tenon is admittedly a problem, but can be totally overcome by gluing in two cross- grain cleats, one on either side of the bolt hole. Better still, cleats made of 1.5mm thick aeroply. These cleats should be glued into sawn kerfs, not just stuck onto the cheeks of the tenon.
Here's a good example of what you describe, Murray. It's Harry Becker and William Cumpiano teaming up to build a new neck for a Gurian guitar. I think this is an excellent approach.

Last edited by BothHands; 10-11-2014 at 11:24 AM.
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  #42  
Old 10-11-2014, 11:13 AM
Tone Gopher Tone Gopher is offline
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Originally Posted by BothHands View Post
Ahhhh! The blessings of FREEDOM! My only problem is trying to find examples of 'other widths' to play beforehand, so I know which to choose for the long run...
Be also aware of neck contour, thickness, thickness taper, fingerboard radius, nut width, nut spacing, fingerboard taper (width at 12th fret), and bridge spacing - if any of it matters, it all matters.
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Go for the Tone,

George
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  #43  
Old 10-11-2014, 11:22 AM
BothHands BothHands is offline
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Originally Posted by Tone Gopher View Post
Be also aware of neck contour, thickness, thickness taper, fingerboard radius, nut width, nut spacing, fingerboard taper (width at 12th fret), and bridge spacing - if any of it matters, it all matters.
Thanks for the reality check, George. I find that I really enjoy 2-5/16" saddle string spacing, so if the Luthier knows I want 1-13/16" nut width and 2-5/16" spacing at the saddle, the fingerboard taper should be determined automatically - based on maintaining the appropriate string distance from the edges (yes?)

And I agree. It ALL matters.
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  #44  
Old 10-11-2014, 01:46 PM
murrmac123 murrmac123 is offline
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Originally Posted by BothHands View Post
. . . if the Luthier knows I want 1-13/16" nut width and 2-5/16" spacing at the saddle, the fingerboard taper should be determined automatically - based on maintaining the appropriate string distance from the edges
Not quite , Tom . . . you would still need to specify at what fret you want the fretboard width to be equal to the string spacing at the saddle, in order to get your desired fretboard taper.

Specifying the width of the fretboard at the 12th fret to be equal to the string spacing gives good results.

I once owned a Collings where the fretboard width at the 16th fret was equal to the string spacing.
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  #45  
Old 10-11-2014, 04:40 PM
charles Tauber charles Tauber is offline
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Originally Posted by murrmac123 View Post
Not quite , Tom . . . you would still need to specify at what fret you want the fretboard width to be equal to the string spacing at the saddle, in order to get your desired fretboard taper.
Murray,

As you know, we've had this discussion before. I don't do it that way. It isn't the way I was taught and I like the flexibility that I have with not doing it that way.

In addition to the string spacing at the nut and the saddle, there are four dimensions that go into determining the profile of the fingerboard. These are as follows:

A: the distance at the nut from the low E string to the edge of the fingerboard.

B: the distance at the nut from the high E string to the edge of the fingerboard.

c: the distance at the 12th fret from the low E string to the edge of the fingerboard.

D: the distance at the 12th fret from the high E string to the edge of the fingerboard.

These determine the profile of the fingerboard, at least for me.

For the fingerpicking guitars that I make, B>A, D>A and A usually is the same as C. At what fret the saddle spacing is the same as the fingerboard width is entirely irrelevant, in the scheme I use.

Certainly, using a formula, such as the width of the 12th fret is equal to the string spacing at the saddle, is often used and works, but the method I use provides - me, anyway - greater ability to tailor the characteristics of the instrument's playability to the specific needs of the player.
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